Such a filling head is described in the successively published German patent application 10 2015 204 925.6. The gas valve body disclosed therein is coupled to a detection device, which detects if a portion of a filling neck of a dosing device is positioned inside the filling tube and which displaces, depending from the detection result, the gas valve body between its closed and open position.
From DE 10 2013 201 237 A1 a venting valve is known, in which a floating chamber is connected via a separate liquid conduit with the operating liquid tank. A filling tube is not provided in this venting valve.
In the floating chamber of the known venting valve, a floating body is positioned, which is connected via a sealing mount with a polymer sealing. The sealing mount is loosely positioned on the floating body in its movement direction.
If operating liquid flows through the separate liquid conduit into the floating chamber, the floating body is lifted, together with the sealing mount and the polymer sealing against the direction of gravitational force, until the polymer sealing closes a venting opening.
If the liquid level in the floating chamber falls again, the floating body moves back, due to its own weight, in the direction of gravitational force, to its original rest or standby position. In order to prevent a pressing of the polymer sealing against the venting opening due to a temporary gas overpressure generated in the floating chamber or in the tank, the floating body is provided with a sealing pin, which in its lifted position protrudes into a passage opening of the polymer sealing, closing the same. Since the polymer sealing is connected with the sealing mount and this in turn is connected with a vertical movement clearance with the floating body, the floating body may move downwards with respect to the sealing mount and therefore also to the polymer sealing, in the direction of gravitation when the polymer sealing is further pressed by a gas overpressure in the floating chamber against the venting opening of the valve housing. The sealing pin is drawn out from the passage opening of the polymer sealing, due to this relative movement provided by the clearance, so that gas may escape through the opening in the polymer sealing and therefore through the venting opening in the valve housing for pressure compensation. In this way, the gas overpressure in the floating chamber is reduced and the lifting of the polymer sealing from the venting opening is eased.
In the venting valve known from DE 10 2013 201 237 A1, the venting opening is always free for gas passage, when the floating body, due to gravitational force, is transferred into its lower position (standby position). From this position, the closing of the venting opening may only take place through a rise in the liquid level.
Both above described solutions have in common the fact that the outflow end of the venting arrangement may be spatially and functionally separate from the filling tube, so that, possible foul smelling gases may exit from the tank inner space and reach the outside, where these gases either cannot be perceived or can be perceived with such a delay by the operator filling the operating liquid, that the work of the operator on the vehicle is finished, before it can be disturbed by the smell of exhausted gases.